Association between dialysis effluent leukocyte count after initial antibiotic treatment and outcomes of patients with peritoneal dialysis-associated peritonitis: a retrospective study

Abstract Background Among patients with peritoneal dialysis-associated peritonitis (PDAP), It has been regarded as an indicator of deterioration of clinical condition that peritoneal dialysis effluent leukocyte count (PDELC) cannot be restored to normal after initial antibiotic therapy. However, the precise relationship between PDELC on day 5 and the clinical outcomes of PDAP episodes remains uncertain. Aims To explore the association between PDELC on day 5 and clinical outcomes of PDAP episodes. Methods This retrospective study was based on the medical chart database of the Affiliated Hospital of Guangdong Medical University. Multivariable regressions were used to evaluate the association between PDELC on day 5 and 60-day mortality, half-year mortality, treatment failure, and the length of stay in hospital with adjustment for confounding factors. Results A total of 549 PDAP episodes in 309 patients were enrolled. The total 60-day mortality, half-year mortality, and rate of treatment failure was 6.0%, 9.8%, and 14.2%, respectively. Compared with patients with normal PDELC, those with PDELC ≥2000 × 106/L on day 5 had significantly higher 60-day mortality (31.1% vs 2.7%), half-year mortality (35.6% vs 5.6%), and treatment failure (46.7% vs 5.7%). In multivariate adjusted regression, the ORs (95%CI) were 6.99 (2.33, 20.92; p = 0.001), 4.97(1.93, 12.77; p = 0.001), and 5.77 (2.07, 16.11; p = 0.001), respectively. Patients with PDELC were 100–2000 × 106/L on day 5 had a higher rate of treatment failure than those with normal PDELC (26.9% vs 5.7%) (OR = 3.03, 95%CI 1.42, 6.46; p = 0.004). After sensitivity analysis, the results remained robust. Conclusions Among patients with PDAP, increased PDELC on day 5 was associated with a greater risk of 60-day mortality, half-year mortality, and treatment failure.

In this study, 48 cases were excluded due to missing data on the PDELC on day 5.In order to evaluate the randomness of missing data, we compared the baseline characteristics of included and excluded cases There is no obvious difference in the baseline characteristics between the two groups, except for mortality.Among the excluded cases, a total of six patients died within 60 days, in which three patients gave up the treatment and died after leaving hospital, and one patient with septic shock and heart failure died on day 4. Notes: data presented are mean ± SD, median (Q1-Q3), or N (%).
The distributions of all the variables of missing data were of similar values with the imputation data (Table S2).
Table S3.Multivariable logistic regression models evaluating the association between PDELC on day 5 and clinical outcomes (using a complete-case data).Table S4.Multivariable linear regression models evaluating the association between PDELC on day 5 and in hospital LOS (using a complete-case data).

Figure S1 :
Figure S1: Receiver operating characteristic (ROC) curve of clinical outcomes and PDELC on day 5, constructed to evaluate the sensitivity and 1-specificity of PDELC on day 5 in the predict 60-day mortality (A), half-year mortality (B), and treatment failure (C).

Table S2 .
The distributions of variables with missing data and the multiple imputation data.

Table S5 .
Baseline of characteristics and outcomes of early-onset and later-onset PDAP cases.

Table S6 .
The multivariable linear regression models evaluating the association between PDELC on day 5 and Logarithmic transformed LOS in hospital.

Table S7 .
Excluding episodes with culture-negative result, multivariable logistic regression models evaluating the association between PDELC on day 5 and clinical outcomes.
Note: 1) Episodes with culture-negative result were excluded.2) Adjust I model adjusts for age and PD-duration; Adjust II model adjusts for adjusts I + Fungal peritonitis+ diabetes mellitus+ CRP; Adjust III model adjusts for adjusts II + albumin + Gram-negative infection + multi-organism infection.

Table S8 .
Excluding episodes with MRSA, Pseudomonas spp., and fungal peritonitis, multivariable logistic regression models evaluating the association between PDELC on day 5 and clinical outcomes.
2) Adjust I model adjusts for age and PD-duration; Adjust II model adjusts for adjusts I + Fungal peritonitis+ diabetes mellitus+ CRP; Adjust III model adjusts for adjusts II + albumin + Gram-negative infection + multi-organism infection.